I think the brew I am making is already fully fermented, after a long period, and it tastes as if it is. But there is still an occasional bubble being produced from the airlock. Does this mean it is still fermenting, or could there be another reason. I do not want to leave it any longer than necessary, and want to proceed to barrelling as soon as possible, and want to finish making the beer as soon as possible. n.b. I notice that the occasional bubbling of which I speak occurs only when I raise the temperature. I should add that I do not have a hydrometer, and have no way of acquiring one within a reasonable amount of time.